1. Field of the Invention
This invention relates to increasing the contrast and resolution of low specular density (below 0.3) film which is otherwise unusable, so that such film is usable.
2. Description of the Prior Art
At present photographic viewers, enlargers, copiers, printers and the like use diffuse or specular transmitted light for viewing, copying and printing. Negatives of normal densities above 0.3 are usable with these devices using diffuse or specular transmitted light. Normally, negatives with densities 0.3 or less are discarded as having little or no information because the contrast level is so low that the image cannot be seen or is barely discernible and unprintable with transmitted light.
In the thin negative case (0.3 density or less) it would be necessary to take the picture over again in order to obtain a usable image. Where the subject is gone or changed, the image is lost forever. Low density films are the result of human errors and insufficient light available to stop motion or record the scene with the available ASA film. Thus, there is a need for a means of recovering information recorded in low density film and to permit low light photography without utilizing the complex, low resolution expensive devices, such as the electro-optical image intensifiers, and microchannel plate amplifiers. Although it is known that silver grains in the film scatter light to an appreciable extent, this phenomenon had not been utilized to increase the resolution and contrast of low density film.